Method of obtaining colored polymerized styrol and its homologues and products obtained thereby



-- mn'rnon or onmfnmc humanity-3, 1927. i

7 uNiTED sem -.5;

PATEurorrtcir IWAN' os'rnonIsLENsxY, or New Yonir, n. Y., ASSIGNOR To TEE raoea'rvcx cannon. comrmir; or

mac'rfcn'r.

. 11o Drawing.

' This invention relates to methods of obtaining colored polymerized styrol and its homologues and to the products obtained thereby.

i I Polymerized styrol may be colored by adding pigments thereto. Such a method of coloring is limited to'the formation of pigments.

With a preferred embodiment in mind and=withont intention to limit the invention 20 beyond what is required. by the prior. art, the invention briefly consists in combining with unpolymerized styrols coloring matter which is soluble in unpolymerized styrols and in the polymerized styrols. It also consists in form ing polymerized styrols from solutions of suchcolors in liquid styrol. The invention also relates to methods of obtaining transparent colors, which mayor may not be fluorescent. v

The word homogeneous used hereafter is meant to signify, when applied to colored polymerized styrol, a continuous and 1111- broken color throughout the mass, as differentiated from styrol colored with pigments. When the ordinary pigments are used the color is non-homogeneous for the reason that the color is imparted by the pigment. Upon careful examination of fragments of the polymerized product it will be seen that the color does not extend through all of the styrol but only around the pigment particle.

The word transparent as used hereinafter is not meant to signify the transparency which .is observed in the absence of any coloring material but rather to designate the type of' colored polymerized styrol whose color is homogeneous throughout its entire mass and through whichlight will pass readily. It is obvious that as the amount of coloring matter is increased the glass may vary through the entire range from almost water white, through transparency, transcomm]: ronrmnmznn sr'Yn-cphim rrs nomozoeuns' AND manners oirmmnn *runnn'nx. 2. Y

Applications! January 29, 1925. "Serial No. 5,457.

lucency into opacity, still preserving its color.

The word styrol glass is used hereinafter to s gnify-the polymerized st rol.

homologues. V q

It has been discovered that a number? of styrol, that is unpolymerized styrol, and

that many of these coloring materials'are I likewise solublein styrol glass. These properties are by no means general in the realm of dyestuffs such as organic chemicals. As

a matter of fact most of the materials men tioned hereinafter have found very -;little application in the ordinary fields of dyeing. It has further been discovered tha'ta; number of the coloring materials which are soluble both in st rol and in styrol glass retain their it possible to obtain remar able results in purity of tint, even distribution of'the coloring. material, as well as in the optical and other physical properties of the glass. Dyes A KA UT, A conromrion or,

. The word styrol is used t rou bout this application as signifying styro and its to coloring materials; are soluble in liquid-v which lend themselves to the' process must I have the following qualifications: (1) They must be soluble both in liquid styrol and in v,

styrol glass; 2) they must be unaffected b high temperatures such as 140-175" C; (3 they must be difficult to reduce into the corresponding leuco compounds at these temperatures; (4) theymust not be affected by the formaldehyde which is formed during the polymerization of styrol; (5) they must possess fairly high stability towards light.

, The greater part of the .dyes which are sold on the market do not conform with the above requirements and therefore do not lend themselves to use in this process. When styrol is polymerized at 140 (1., most of the dyes on the market are subjected to decolorization or charring, and the outcome is that they take on a: heterogeneous uneven or dirty tint and frequently form resinous substances.

ordinarily In carrying out the invention, it became.

therefore necessary to develop new coloring matters and to im rove the known processes for dyes which might be used. It is noted that a great many of-the dyes used in this invention have not been given .any great practical application, such as in the dyeing of fabrics.

The following materials have been found suitable for carrying out the process of this invention:

Homofluoiindine:fluorindine,

Monophenylfluorindine.

Diphenylfiuorindine.

Monochlordiphenylfluorindlne.

Dichlordiphenylfluorindine.

Monoanilldodiphenylfiuorindine Dianilidodiphenylfluorindine.

N aphthanthraquinone.

Decacyclene.

Cinnamylidenfluorene.

Triphendioxazine.

Triphenazinoxazine.

Mesoanthramine.

Diiminodianthrone.

Acetylmesoanthramine.

Diaminodianthryl.

N aphthant hracene.

Phenyl-alpha-naphthylamine.

Thiophenyl-beta-naphthylamine.

Thiophenyl-alpha-naphthylamine. Phenylhydrazone of phenylvinylketone. Fluoroeyclene.

Anthracene (purissimo).

Leuco base of thioindigo blue G.

Leuco base of thioindigo violet C.

Quinone (free base).

Phen lazodiaminopyridine.

Mag ala red (free base).

High-boiling fractions ofsome kinds of naphtha.

Extract of cork in styrol.

Extract of incomplete combustion products in styrol.

Chloranilinoaposafranin.

Anilinoaposafranin.

Products formed in the explosion of mixtures of steann'styrol and air.

The most varied tints can be obtained with fluorindines; in the form of free bases, these substances impart to metastyrol a rose, red, violet or bluish-violet coloring with a yellow or red fluorescence. depth of shade of these colors depend, of course, upon the concentration of the particular fluorindine. \V hen used in the form of salts the produce the most varied shades and hues 0 blue.

The fluorindine salts of the following acids have been applied successfully: hydrochloric, formic, propionic, Valerie, caprylic, stearic,

palmitic, carbolie, resorcyclic, benzoic, me-- thoxybenzoic (ortho), hthalic, terephthalic, cinnamic, saly c-'y'l-ic,'-'alp a-naphthylorthobenzoic, ehlorajcetic, tri'chloracetic, ben zolsulphonic...

be present, the flu 'tion of the The intensity and the The fiuorindine salts of oxalic, urici an- 7 thranilic, sulfanilic and glycocolic'aci not appear to dissolve'in st rol. v

If there is an excess of uorindine in the styrol solution the glass obtained will. display a red or brown fluorescence above its color, and the fluorescence'is usually quite sdo' intense. If, however, an excess of free acid.

without a trace.

In the pol merization of styrol a dissociaorestenceimay disappear uorindine salts can be observed. Therefore the freshly obtained glass dil-. plays, especiallyv when hot; the coloring and the fluorescence of the free fluorindine. However, in storage this coloring graduall changes to blue. The fluorindine salts whic under the-action of the high polymerization temperature decompose to their constituent parts, are again formed more or less quickly at normal temperature. Sometimes this formation of salt lasts some 1-2 months, at other times it is complete in a few days or even hours. The ultimate coloring of the styrol glass becomes identical with that of the original styrol. .The higher the dissociation constant in the original acid, and the degree of basicity of the given fluorindine', the quicker will the reverseformation of the salts take place. Among the dyes of the series which were investi ated the basic character is most salient 1n mono-andolianilidodiphenylfiuorindine; the strongest acids we used for'this process were the hydrochloric and chloracetic.

When st ml is polymerized in the presence of a airly large excess of acid (such as for instance ortho-methoxy-benzoic acid) the fluorindine salt does not dissociate at all. The blue color of freshly-made styrol glass, which in this case is altogether similar to that of the original styrol, does not in any way change during the ageing of the substance. I

The majority of organic compounds dissolve much more readily in styrol than in styrol glass. Therefore towards the end of the polymerization process, or if the styrol contains too great an excess of organic acids, the latter will sometimes crystalllze, usually causing a general or partial cloudiness in the product. Consequently, care must be taken not to introduce too great an excess of organic acids. Furthermore the fact must be taken into consideration that too large a percentage'of these acids may lower the plasticity point of a glass quite appreciably and thereby interfere in the subsequent formation of the glass into articles.

As a specific example of the manner in which the invention is carried out, the following is given: A saturated solution of orthomethoxybenzoic acid at 0 C. is prepared in styrol. Into, this solution 'ure styrol to the amount of 30%'is added. to

the resultant mixture a saturated styrol solution of a fluorindine, say dianilidodiphenylfluorindine, is introduced by degrces,'either drop by drop or in small portions until the solution has obtained the desired color, blue in-this case. The colored styrolyis then polymerized for 18 hrs. at- 140 C. in a vessel fitted with a reflux condenser and after this the heating is continued for 5 hrs. at 175C. If desired, the polymerization can be carried out at 140 C. for 40 hrs, using a reflux condenser. After cooling the polymerized product is removed from the container and heated for 2 or-3 hrs. at. 90 C. H

Styrol glass which has beencolored by the free base of a fluorindin'e to a rose, red or violet can be changed to blue by treatment with hydrochloric acid. This is done by placing the glass in a vessel through which a current of dry hydrogen chloride 18 passed at 100 C. The same general reaction takes ept in fuming-aqueous hydrochloric acid at ordinary temperature, a characteristic bluetint gradually forming and spreading from the outer surface towards the center of the piece of glass. It is evident that the hydrochloric acid has the property of ,difi' using in with an orange tone and shows agreen fluorescence.

Naphthanthraquinonc (0.l .5')i 0.2%) colors styrol glass to a golden-ycllowtmt of a pure shade without any fluorescence. This substance somewhat retards the polymerization of the styrolitsel'f, and it added in large quantities, it will lower the plasticity point of the latter. In the presence of naphthanthraquinone the styrol must be polymerized for 20 hours at 140 C. and further for 5 hours at 175 C.

Decacyclene (solution saturated at 0 C. plus 18% of pure styrol) colors styrol glass to yellow with a pure green fluorescence very much like applegreen.

Cinnamylidene-fluorene added to styrol gives a pureyellow color which, however, after polymerization. turns to an ugly brown tint.

Mesoanthramine (0.02% 0.08%) turns styrol to a yellow color of a not altogether pure tint with a deep green fluorescence. lin the"presence of merely traces of mesoa nlace when a fluorindine-colored glass isthramine, styrol glass takes on a pure yellow coloring free from fluorescence.

' Diam'inodianthryl (0.1%.0.01%) dyes styrol glass to a deep and pure yellow with a very intense emerald-green fluorescence. In

Dyestufl's of the indigo and 'thioindigo series when heated in styrol to'140 C. will be transformed to the corresponding leuco compounds. In this connection it has been found that many of the leuco compounds of the thioindigo dyes in styrol glass show a very vivid green fluorescence. This phenomenon is especially pronounced in solutions of indigo blue G and thio indigo blueviolet B. In a suitable concentration they color t-he glass to a pale-orange tint, or else they leave the glass colorless (at any rate when in a thin sheet), but with a strong fluorescence: Formula: 10 ccm. of 0.17% thioindigoblue or violet solution are introduced into 50 com. of pure styrol (as a matter of fact 0.05 gins. of the dye should be' previously dissolved in 30 ccm. of sty rol). The resulting mixture (0.28%) is then polymerized with a reflux condenser 'for 17 hours at 140 C.'and then for 3 hours at 175 without the latter. After the styrol glass has been removed from the vessel in which it was polymerized, it is agaiuheated for 10 hours at C. e Chloranilinoaposafranin dyes boiling styrol to a reddish brown tint which when the solution cools, turns to a vivid violet.v If the styrol is polymerized under ordinary conditions this coloring disappears and colorless or almost colorless glass results, which however diplays alight brown fluorescence of a soft shade.

Anilinoaposafranin behaves in asimilar manner to the above.

Mixtures of various substances which color styrol glass yellow (naphthanthraquinone and clecacyclene are particularly easy to handle) and various salts of fluorindines produce green glass of every tint and shade. The product may display a bright red or a brown fluorescence, but in the prescncc of a certain excess ofthe acid which forms the given fluorindine salt, this fluorescence disappears without. a trace. In par- I ticular, green styrol glass can be obtained by adding to the styrol solution of some fluorlndlne salt, an extract of lumps of cork in styrol, forsuch extracts are ofa yellow color.

, styrol that is formed.

- green fluorescence The free base, Magdala red, .was isolated from the market product of this name by treatment with ammonia. This free base colors styrol glass to a reddish pink color which has a rather disagreeable brown tint. This color is not sufliciently homogeneous for some purposes.

Diiminodianthrone (0.08%) imparts ,to styrol glass a reddish orange tint very much like the color of apricots. In the' presence of a small amount of-the imine styrol glass remains colorless, taking on, however,- a peculiar orange fluorescence. When (luminodianthrone. is used the polymerization has to be conducted primarily at 130? C. otherwise it is the abnormal modification of meta- In 18 hours the reaction temperature can be brought. to 175 C. This latter part of the process must be kept up for some hours.

Nap ithanthracene (0.08%0.2%) 1n a solution of styrol glass produces a. pure yellow coloring in transmitted light atfihe same time imparting tothe glass a bright unusual intensity.

Various azo-dyes are easily decomposed or even charred-in the polymerization of styrol; sometimes they impart to the glass (0.08%) acety curious tints of brown. in particular, paratolylazodiaminopyridin imparts to styrol glass a brown t nt very inucl1 like tortolse shell. I

Quinine (free base) gives an almost colorless product if the polymerization is carefully handled; the product displays a pale green fluorescence. However this fluorescing substance is not evenly distributed throughout the mass and it easily takes on a brown or amber tint in parts. When polymerizing styrol which contains 1% of quinine at 140 C. for hours in a tube placed horizontally and provided with a reflux condenser. a very peculiar and curious product is obtained. .lis coloring is not homogeneous being in places of an amber yellow and in others brown oi. a cocoa or burnt wood tint. These colors interminglc within the mass, forming a peculiar play of colors, or else cloud masses.

Thiophenylhetanaphthylamine (0.08%) and thiophenylalphanaphthylamine in styrol glass shows yellow in transmitted light and also displays a very intensive green fluorescence. y

. Pure anthraceue (01673-0270) fluorocyclene (0.1%? phenylalphanaphthylamine mesoanthramine (0.1%) and especially phenylhydrazone of phenylvinylketones lmpart to styrol glass :1

-violet, ure blue or bluish-violet fluorescence.

Nevert eless the glass remains altogether colorless in transmitted light. ,When a concentrated styrol solution of. rdianilidodiphenylfluorindine is added to a V-G teen 0.2% styrol solution of phenylhydrazone of phenylvinylketone, until the yellow coloring entirely disappears, there is formed a solution which in polymerization under ordinary conditions produces altogether colorless glass with an amethyst fluorescence.

A definite combination of naphthanthrauinone with mono or dianilidodiphenyluorindine gives colorless or almost colorless glass with a vivid coral pink fluorescence.

The highest fractions of several kinds of naphtha color styrol glass to a dirty-looking yellow, at the same time imparting to it a fairly strong green fluorescence.

I-Pink Hnmofluorindine.

Monopiienyifiuorindine.

Diphenylfluorindinc.

Monochiordiphenylfluorindine.

Ma daia red (free base).

Die lonliphenylfluorindine.

Monochlordiphenyifluorindlne.

Diphenylfluorimlino.

All fluorindincsin suitableconcentration.

Tnphenodioxazm; leuco compounds of thioindilo blue 0. and violet B.

Mesoanthraininc.

Diiminoilianthrono.

N aphthanthraquinono; napiitiianthrarene.

Decacycicne; tliiophenylbetanaphtliyiamine.

Cinnam ylidcneiluorene; thiophenyialp h a n a p hthylamine.

Mcsoanthrmnine.

Diaminodianthryi.

Extract of cork in styrol.

Silver nitrate (0.001%).

Diuminndlphenyliluorindino (citheriu traces orin large amounts) plus decacycicnc. Naphthanthriu'cno; diaminodianthryi.

Mixtures oisubsianoes sub. IV with Vi or VII.

Dianiiidodiphenyliluorindine (negligible amount).

Monoaniiidodiphenyiiluorindinc.

Salts of organic or mineral acids of all fluorindincl,

in a weak solution.

lI-Red III-Orange.

ViLiglit blue.

VIIliiuo in a stronger concentration.

Gold chloride.

Dianiiidodiphenylliuorindine- Monoanilidodigbcnyliluorindiun.

Mixtures of Sn stances sub. I and II with thm sub. VI and VII.

Quinine (free base).

'iolyi or phenylazodiamino )yridlne.

. Concentrated extract of cor in styroi.

Anilinoaposairanin; chloranilinoapooairanin. Silver nitrate to the amount of 0.0I%0.02%. Mngdala rod (free base).

ViIi-Violct..

stances.

As is well-known fluorescing substances" All suits, organic or mineral acids oiali fluorhidill Products of dry distillation of many organic subins wave. The following tableshows some :of' the properties of various fluorescing substances:

Table II.

. Color of Color ot-transradiation. 'mittedllght. nuomcmg substance.

Blue Colorless.---. Plliieizylhydrazone of phenylvinyle one. Blue- Colorless Fluorocyclene. Blue Colorlew Aoetylmesoanthramine. Violet Colorless or Anthracene. Products formed in slightly yelexplosion of mixture of styrol low. fumes and air; Blue-violet... .Colorless Phenyl-alpha naphthylamine. Amethyst"... Colorless Mixtures of phenylhydrazone of phenylvinylketone and dianiili dodiphen lfluorlndine. Coral pink... Almost color.- Migture of ianllldodl henylfluorluless. dine and naphthaut raquinone. Allzarlnred.-. Colorless Mono or dlanihdodiphenylfluorindine in very weak solutions. Yellow Pink or red..- Home or mono or dlphenylfluonndine; monochlordiphenyl, dichlordlphenylfluorindine Fire red Violet Mono or dlanlhdod phenylfluorinne.- Green Orange 'Irl henodioxazine. Green Paleorangeor Th o-indigo blue 0 or violet B.

i almost color- (leueo compounds).

ess. Yellow Dlaminodianthryl. Brown-yellow. Mesoanthramine. Golden yellow Decacyclene. Green otother Mixture oi fluorlndlne salts and tint. decacyclene. Green-yellow Ne hthanthraeene. Yellowish Th oplhenyl-beta-naphthylamine or alp anaphthylamlne; Brow lsh... Quinine. Products of incomplete combustion of styrol. Highest fractions of naphtha. Pyrogenizetion products of many organic compoun Varlousreds.. Blue Various fluorindlne salts. Vermilion.-- Cobalt blue--. Orthomethoxybenzorc nerd salt oi diphenylfluoriudine Brown Colorless, or Chloranilinoasposalranm; aniline light blue. posairanin; nuorindine salts of clnnarnic acid; weak solution of monoanilidodiphenyl fluorindlne, made up by special method. Many fluorindine salts. Gold chloride. White .J. Orangeorpale Mixture of trlphendloxazine, di-

- I 1 green. phenyl fluorindine and phenyl I hydrazone oi phenylvinylketouc.

Many of the colors and dyes mentioned above, while not used commercially for dyeing fabrics, are suitable for coloring paraflin, Wax, celluloid, acetyl cellulose and for other plastics in-which the dyes will dissolve or will disperse with some readiness.

Certain inorganic salts are soluble in styrol and in styrol glass. Some of these also impart colors to the glass.

Solutions of colloidal metals, particularly gold, silver, and mercury can be obtained in styrol glass. Anhydrous gold chloride, silver nitrate, or hydrohali'de salts of mercury can be dissolved in styrol. When these solutions-are heated to'140-180 G. in the course of the polymerization of the styrols, colloidal solutions of the metals are formed simultaneously. It would appear that the reduetion of the original salts has been accomplished by the styrol itself or by the aldehyde formed during the polymerization. It

is advisable to have a small amount of styrol glass-dissolved 1n -the styrol, to function as a rotective colloid.

A smal amountof gold chloride which has been driedv in vacuo at C. is introduced intoj lstyrol conta ningabout 35% of tn're being raised quite gradually to'the' styrol 'The resulting mixture is well shakenup and carefully heated, the temyieriiic in? point. The resulting, fairly opaque so u ion is quickly filtered off t rough a. folded paper filter while still hot and then is immediately introduced in small portions intostyrdl containing about 5% of styrol glass until a blue'colorin somewhat deeper than the desired shade is o tained. The mixture is thoroughlyshaken up and if necesain filtered off. It is -then polysary is a merized or 25 hours at 140? G. and again 5 hours at 180 (1., in the last instance with- .out a reflux condenser.) In the end styrol 'styrol glass, the colloidal gold during the polymerization step ,7 does not have time to become evenly distributed throughout the glass, and the product is colorless in some-= places and cloudy in. others.

The color that styrol glass takes on under the action of silver nitrate depends upon the following conditions: (1) concentration of the silver nitrate used (2) duration and temperature of the polymerization (3) purity of the silver nitrate.

Pure silver nitrate usually colors styrol 7 glass to various shades of brown, or to a very ark, almost black color. When containing salt to the amount of 0.001%, glass is produced which even in a thick sheet (about 10 cm.) has a scarcely noticeable brown tint. In the presence of 0.01% of silver nitrate the resulting glass is almost opaque when in a thick sheet, but in transmitted light it shows brown whilst in reflected light it is likewise opaque, opalescing with a dark brown, almost black color with a curious greenish reflection. V

Impure silver nitrate which tarnishes when exposed to daylight or in a moist atmosphere, produces more interesting and varied colorings. For this purpose silver nitrate was used which had been recovered from thesilver chloride obtained from the fixing-solutions used in photography. Glass which contains 0.001% of such silver salts (polymerization is keptup for 15 hours at 140 C.) acquires a pure golden-yellow color and does not opalesce. When the content of silver nitrate approximates 0.013% the glass takes on a lovely darkred color, but in reflected light it shows opaque and whitishgray of a most curious shade. sheet it displays a peculiar green fluorescence. Analogous results were obtained with 0.04% of silver nitrate; when the content is reduced to 0.008% an interesting re ddish In a thinbrown color, without any fluorescence is obpolymerized styrols Which comprises distained.

To 20 gms. of styrol containing 1-3% of st rol glass, 5 com. of a solution of 0.02 gms. oisilver nitrate in com. of styrol which likewise contains 1.-3% of styrol glass, are added, the temperature being raised gradually. This mixture is heated with a reflux (air) condenser for 12 hours at 175 C. In the end styrol glass containing 0.008% of silver nitrate is obtained. For coloring glass of this kind see above.

Silver nitrate also possesses the property, even when present in amounts as small as 0.001%, of rendering the styrol glass more durable, pliable and resilient.v

While the word dyestufl has been used to indicate organic compounds, it is understood that the terms dyestutf and coloring material both include inorganic compounds, the real criteria being those of solubility in styrol and styrol glass and ability to impart a color to the glass."

The process is also applicable to the light colored resins and resinous products, known as condensation products provided the coloring materials are soluble in these products and are unaffected by the temperatures reached in forming the resins. The process may also be used in coloring the beta or brittle modification of polymerized styrol, as well as to other modifications and to mixtures of the several modifications of styrol glass.

As many apparently widely different embodiments of this invention may be made without departing from the spirit thereof, it will be understood that I do not intend to limit myself to the specific embodiment herein set forth except as indicated in the ap ended claims.

' aving thus described my invention, what I claim and desire to protect by Letters Patent is:

ls A process for producing colored polymerized styrols which comprises forming styrol solutions of colorin material soluble in styrols and in their po ym'ers and polymerizing the solution to form polymerized styrols. 2. A process for producing colored polymerized styrols which comprises dissolving in styrols coloring material which is capable of withstanding the temperatures reached during polymerization of the styrols,'and

polymerizing the styrols.

3. A; process for producing colored poly- 'merized styrols which comprises adding to unpol merized styrols coloring material capab e of dissolving in styrol and in polymerized styrols, and adapted to retain substantially the original intensity of color, polymerizing said solution of coloring material in styrol to form polymerized styrols.

4. A process for producing colored vitreous solving in unpolymerized styrols coloring material which is soluble in vitreous polymerized styrol, and heatin the solution of coloring material in unpo lymerized styrol to bring about polymerization of said solution to form the vitreous polymer thereof without substantially changing the intensity of the coloring material.

5. A process for producing colored vitreous polymerized stiyrols which comprises dissolving in unpo ymerized styrol coloring material which is soluble in vitreous polymerized styrol, and heating the solution at 140-180 G. to form a homo eneously colored vitreous polymerized styrol? 6. A process for producing colored vitreous polymerized styrols which-comprises dissolving in unpolymerized styrol coloring material which is soluble in vitreous polymerized styrol and is inert towards byproducts formed during polymerization of styrol and heating the solution of coloring material in unpolymerized styrol at 140 to 180 C. to form a colored vitreous polymerized styrol.

7 A process for producing colored vitreous polymerized styrol which comprising dissolving in unpolymerized styrol fiuorescing coloring material which is soluble in vitreous polymerized styrol and polymerizing the solution at approximately 140 to 180 C. to form a fluorescent vitreous polymerized styrol.

8. A process for producing colored vitreous polymerized styrols which comprises dissolving coloring material of the fluorindine series in unpolymerized styrol, and poly-.

merizing the solution at approxnnately 140 to 180 C. to form a colored vitreous polymerized styrol.

9. In a process for producing colored vitreous polymerized styrols, wherein colorin material is dissolved in styrol, and the solution polymerized to vitreous polymerized styrol the step of changing the color imparte' by the free base of a fluorindine to said polymer, which comprises subjecting the polymerized styrol to the action of a material adapted to diffuse through the polymer and to react with said free base to change its color. I

10. In a process for producing colored vitreous polymerized styrols, wherein colorilm-material is dissolved in styrol, and the solution polymerized to vitreous polymerized styrol, the step of changing the color imparted by the free base of a fluorindine to said polymer, which comprises treating the polymerized styrol with an acid adapted to diffuse through said polymer and to changethe color of the free base.

11. As new products, polymerized styrols containing dissolved therein coloring material whose intensity-change temperatures lie without the polymerization ternperatures ored transparent itreous polymerized styof styrol. rols which are fluorescent. ll

12. As new products, homogeneously col- 15. As new products, vitreous polymerized ored vitreous polymerized styrols. styrols colored with a fluorindine.

5 13. As new products, homogeneously col- Signed at Cromwell, county of Middlesex ored transparent vitreous polymerized styand State of Connecticut, this 26th day of rols. January, 1925.

14. As new'products, homogeneously col- I WAN OSTROMISLENSKY. 

